The paper deals with new software ensuring the ride of some interdependent tram vehicles in accordance with the criterion of the minimum energy consumption. All trams have been driven by vectorially controlled and field oriented three-phase induction motors supplied from the modern inverters. First of all, the influence of light signalling on the coordinated energy-saving traffic of trams has been taken into consideration. In one example there was shown the possible case for three trams ride free from the possibility of collisions. Here the energy savings were the biggest. Every time it is very difficult to ensure the green light for every tram vehicle at the same crossing. There were analysed two variants of disturbances caused by the light signalling: additional short and long tram stop. In the instance of large time lags of the traffic, the ride delay must be liquidated during the run between some succeeding stops.